Determination of 24 minor red blood cell antigens for more than 2000 blood donors by high-throughput DNA analysis

Abstract

Background: A "BeadChip" array permits reliable simultaneous DNA typing of single-nucleotide polymorphisms for minor blood groups. A high-throughput DNA analysis was studied as a routine method of phenotype prediction and software was developed to interpret and analyze the large volume of data points.

Study design and methods: DNA was extracted from whole blood of donors of known phenotypes and self-identified ethnicity. Analysis of single-nucleotide polymorphisms (SNPs) associated with 24 antigens of 10 blood group systems was performed with BeadChips (BioArray Solutions), and the results were compared to historical serologic typings. Phenotypes were predicted for individual samples, and phenotype prevalence was determined for ethnicities. The BeadChip was expanded to incorporate SNPs that silence the S antigen, validated, and tested with 369 DNA samples. A time-motion analysis was conducted.

Results: Results of BeadChip analyses were concordant with prediction of antigen negativity for 4,510 antigens. Eight discordant results were due to silencing of GYPB(S) and 16 were likely errors in recording serological results or data entry. The analyses produced 19,457 antigen-negative typings not serologically defined, identified 21 rare donors (Co(a-b+) [n = 1], Jo(a-) [n = 6], S-s-[n = 12], and K+k-[n = 2]), and determined allele frequencies and antigen prevalence for four ethnicities. The expanded panel detected 30 SS, 235 ss, 100 Ss, and 4 U- samples. The format processes 192 DNA samples (two plates) per 8-hour shift per technician, including automated data analysis and report generation.

Conclusion: DNA analysis with BeadChip format, combined with computerized data entry and analysis, permits the prediction of minor blood group antigens.